Pumice
Vesicular volcanic glass
igneous
Category
Amorphous Solid
Browse amorphous solid specimens identified by the Rock Identifier community.
Pumice
Pumice (Vesicular Rhyolite/Andesite)
igneous
Anthracite Coal
Anthracite (Metamorphosed Coal)
sedimentary
Concrete / Anthropogenic Conglomerate
Man-made composite material (Portland cement, aggregate, and water)
not a natural rock
Ironstone Concretion / Limonite
Goethite and Limonite (FeO(OH)·nH2O)
sedimentary
Libyan Desert Glass
Impact-melt silica glass (SiO2 + traces of Al, Fe, Ti)
mineral (Tektite/Impactite)
Bituminous Coal
Organic sedimentary rock (humic coal)
sedimentary
Anthracite Coal
Anthracite (Carbon-rich metamorphic coal)
metamorphic
Blue Goldstone
Aventurine Glass (SiO2 with Co and metallic inclusions)
mineral (synthetic glass)
Pumice
Pumice (a highly vesicular, silicic volcanic rock)
igneous
Green Sea Glass
Amorphous Silica (man-made glass), SiO2 + additive metal oxides
mineraloid / anthropogenic (man-made origin)
Red Slag Glass (Cullet)
Amorphous Silicon Dioxide (SiO2) with metallic dopants
Antropogenic (Man-made material)
Boulder Opal
Precious Opal in Ironstone (Amorphous Hydrated Silica, SiO2·nH2O)
Mineral
Sandstone (Ferruginous/Banded)
Clastic Terrigenous Sandstone (SiO2 with Fe2O3 cement)
sedimentary
Chrysocolla
Hydrated copper silicate (Cu,Al)2H2Si2O5(OH)4·nH2O
mineral
Ironstone Concretion (Limonite/Goethite)
Ferruginous Sandstone / Ironstone (FeO(OH)·nH2O)
sedimentary
Black Obsidian
Volcanic Glass (Primary composition: SiO2 - Silicon Dioxide)
igneous
Blue Goldstone
Aventurine Glass (SiO2 with Cobalt/Copper inclusions)
man-made glass
Iron Slag
Iron smelting byproduct (Glassy/vesicular silicate)
anthropogenic / industrial byproduct
Yellow Ocher (Limonite)
Limonite (Hydrated Iron Oxide) - FeO(OH)·nH2O
mineral
Black Obsidian
Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide) with impurities
igneous
Tumbled Obsidian
Volcanic Glass (Silicon Dioxide)
igneous
Coquina (Fossiliferous Limestone)
Coquina (Organic Clastic Limestone)
sedimentary
Snowflake Obsidian
Spherulitic Volcanic Glass (SiO2 + impurities)
igneous
Snowflake Obsidian (Flower Jasper variant)
Vitreous volcanic silicate with cristobalite inclusions
igneous
Ethiopian Opal (Welo Opal in Matrix)
Hydrated Silica (SiO2·nH2O)
mineral
Limonitic Gossan
Goethite/Limonite aggregate after sulfide
igneous and metamorphic derivative (weathered)
Amber
Succinite (a fossilized organic resin containing succinic acid)
mineraloid
Sandstone Concretion
Moqui Marble (Iron-oxide concretion)
sedimentary
Obsidian
Obsidian (principally SiO2)
igneous
Acrylic or Resin (Synthetic Imitation)
Polymethyl Methacrylate (PMMA) or Polyepoxide
Synthetic/Man-made Polymer
Ferrochrome Slag
Anthropogenic slag (Fe-Cr alloy waste)
industrial byproduct
Obsidian
Volcanic glass (SiO2 - Silicon Dioxide with impurities)
igneous
Amber
Succinite (fossilized tree resin)
mineral
Pumice
Felsic Volcanic Glass / Vesicular Rhyolite
Igneous
Obsidian
Obsidian (Volcanic Glass)
Igneous
Chrysocolla on Quartz with Iron Oxides
Cu2-xAlx(H2-xSi2O5)(OH)4·n(H2O)
mineral
Amber
Succinite (fossilized resin); C10H16O
mineraloid
Pumice
Pumice (a highly vesicular volcanic rock)
igneous
Snowflake Obsidian
Vitreous volcanic silicate rock (SiO2) with Spherulite inclusions
igneous
Fossilized Shark Tooth
Fossil Chondrichthyes (various genera such as Carcharias or Odontaspis)
sedimentary
Limonite
Limonite (Hydrous iron oxides, FeO(OH)·nH2O)
mineral